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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-09 13:34:27 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-09 13:34:27 +0000 |
commit | 4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f (patch) | |
tree | 47c1d492e9c956c1cd2b74dbd3b9d8b0db44dc4e /compat/fsmonitor/fsm-listen-darwin.c | |
parent | Initial commit. (diff) | |
download | git-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.tar.xz git-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.zip |
Adding upstream version 1:2.43.0.upstream/1%2.43.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'compat/fsmonitor/fsm-listen-darwin.c')
-rw-r--r-- | compat/fsmonitor/fsm-listen-darwin.c | 539 |
1 files changed, 539 insertions, 0 deletions
diff --git a/compat/fsmonitor/fsm-listen-darwin.c b/compat/fsmonitor/fsm-listen-darwin.c new file mode 100644 index 0000000..11b56d3 --- /dev/null +++ b/compat/fsmonitor/fsm-listen-darwin.c @@ -0,0 +1,539 @@ +#ifndef __clang__ +#include <dispatch/dispatch.h> +#include "fsm-darwin-gcc.h" +#else +#include <CoreFoundation/CoreFoundation.h> +#include <CoreServices/CoreServices.h> + +#ifndef AVAILABLE_MAC_OS_X_VERSION_10_13_AND_LATER +/* + * This enum value was added in 10.13 to: + * + * /Applications/Xcode.app/Contents/Developer/Platforms/ \ + * MacOSX.platform/Developer/SDKs/MacOSX.sdk/System/ \ + * Library/Frameworks/CoreServices.framework/Frameworks/ \ + * FSEvents.framework/Versions/Current/Headers/FSEvents.h + * + * If we're compiling against an older SDK, this symbol won't be + * present. Silently define it here so that we don't have to ifdef + * the logging or masking below. This should be harmless since older + * versions of macOS won't ever emit this FS event anyway. + */ +#define kFSEventStreamEventFlagItemCloned 0x00400000 +#endif +#endif + +#include "git-compat-util.h" +#include "fsmonitor-ll.h" +#include "fsm-listen.h" +#include "fsmonitor--daemon.h" +#include "fsmonitor-path-utils.h" +#include "gettext.h" +#include "string-list.h" +#include "trace.h" + +struct fsm_listen_data +{ + CFStringRef cfsr_worktree_path; + CFStringRef cfsr_gitdir_path; + + CFArrayRef cfar_paths_to_watch; + int nr_paths_watching; + + FSEventStreamRef stream; + + dispatch_queue_t dq; + pthread_cond_t dq_finished; + pthread_mutex_t dq_lock; + + enum shutdown_style { + SHUTDOWN_EVENT = 0, + FORCE_SHUTDOWN, + FORCE_ERROR_STOP, + } shutdown_style; + + unsigned int stream_scheduled:1; + unsigned int stream_started:1; +}; + +static void log_flags_set(const char *path, const FSEventStreamEventFlags flag) +{ + struct strbuf msg = STRBUF_INIT; + + if (flag & kFSEventStreamEventFlagMustScanSubDirs) + strbuf_addstr(&msg, "MustScanSubDirs|"); + if (flag & kFSEventStreamEventFlagUserDropped) + strbuf_addstr(&msg, "UserDropped|"); + if (flag & kFSEventStreamEventFlagKernelDropped) + strbuf_addstr(&msg, "KernelDropped|"); + if (flag & kFSEventStreamEventFlagEventIdsWrapped) + strbuf_addstr(&msg, "EventIdsWrapped|"); + if (flag & kFSEventStreamEventFlagHistoryDone) + strbuf_addstr(&msg, "HistoryDone|"); + if (flag & kFSEventStreamEventFlagRootChanged) + strbuf_addstr(&msg, "RootChanged|"); + if (flag & kFSEventStreamEventFlagMount) + strbuf_addstr(&msg, "Mount|"); + if (flag & kFSEventStreamEventFlagUnmount) + strbuf_addstr(&msg, "Unmount|"); + if (flag & kFSEventStreamEventFlagItemChangeOwner) + strbuf_addstr(&msg, "ItemChangeOwner|"); + if (flag & kFSEventStreamEventFlagItemCreated) + strbuf_addstr(&msg, "ItemCreated|"); + if (flag & kFSEventStreamEventFlagItemFinderInfoMod) + strbuf_addstr(&msg, "ItemFinderInfoMod|"); + if (flag & kFSEventStreamEventFlagItemInodeMetaMod) + strbuf_addstr(&msg, "ItemInodeMetaMod|"); + if (flag & kFSEventStreamEventFlagItemIsDir) + strbuf_addstr(&msg, "ItemIsDir|"); + if (flag & kFSEventStreamEventFlagItemIsFile) + strbuf_addstr(&msg, "ItemIsFile|"); + if (flag & kFSEventStreamEventFlagItemIsHardlink) + strbuf_addstr(&msg, "ItemIsHardlink|"); + if (flag & kFSEventStreamEventFlagItemIsLastHardlink) + strbuf_addstr(&msg, "ItemIsLastHardlink|"); + if (flag & kFSEventStreamEventFlagItemIsSymlink) + strbuf_addstr(&msg, "ItemIsSymlink|"); + if (flag & kFSEventStreamEventFlagItemModified) + strbuf_addstr(&msg, "ItemModified|"); + if (flag & kFSEventStreamEventFlagItemRemoved) + strbuf_addstr(&msg, "ItemRemoved|"); + if (flag & kFSEventStreamEventFlagItemRenamed) + strbuf_addstr(&msg, "ItemRenamed|"); + if (flag & kFSEventStreamEventFlagItemXattrMod) + strbuf_addstr(&msg, "ItemXattrMod|"); + if (flag & kFSEventStreamEventFlagOwnEvent) + strbuf_addstr(&msg, "OwnEvent|"); + if (flag & kFSEventStreamEventFlagItemCloned) + strbuf_addstr(&msg, "ItemCloned|"); + + trace_printf_key(&trace_fsmonitor, "fsevent: '%s', flags=0x%x %s", + path, flag, msg.buf); + + strbuf_release(&msg); +} + +static int ef_is_root_changed(const FSEventStreamEventFlags ef) +{ + return (ef & kFSEventStreamEventFlagRootChanged); +} + +static int ef_is_root_delete(const FSEventStreamEventFlags ef) +{ + return (ef & kFSEventStreamEventFlagItemIsDir && + ef & kFSEventStreamEventFlagItemRemoved); +} + +static int ef_is_root_renamed(const FSEventStreamEventFlags ef) +{ + return (ef & kFSEventStreamEventFlagItemIsDir && + ef & kFSEventStreamEventFlagItemRenamed); +} + +static int ef_is_dropped(const FSEventStreamEventFlags ef) +{ + return (ef & kFSEventStreamEventFlagMustScanSubDirs || + ef & kFSEventStreamEventFlagKernelDropped || + ef & kFSEventStreamEventFlagUserDropped); +} + +/* + * If an `xattr` change is the only reason we received this event, + * then silently ignore it. Git doesn't care about xattr's. We + * have to be careful here because the kernel can combine multiple + * events for a single path. And because events always have certain + * bits set, such as `ItemIsFile` or `ItemIsDir`. + * + * Return 1 if we should ignore it. + */ +static int ef_ignore_xattr(const FSEventStreamEventFlags ef) +{ + static const FSEventStreamEventFlags mask = + kFSEventStreamEventFlagItemChangeOwner | + kFSEventStreamEventFlagItemCreated | + kFSEventStreamEventFlagItemFinderInfoMod | + kFSEventStreamEventFlagItemInodeMetaMod | + kFSEventStreamEventFlagItemModified | + kFSEventStreamEventFlagItemRemoved | + kFSEventStreamEventFlagItemRenamed | + kFSEventStreamEventFlagItemXattrMod | + kFSEventStreamEventFlagItemCloned; + + return ((ef & mask) == kFSEventStreamEventFlagItemXattrMod); +} + +/* + * On MacOS we have to adjust for Unicode composition insensitivity + * (where NFC and NFD spellings are not respected). The different + * spellings are essentially aliases regardless of how the path is + * actually stored on the disk. + * + * This is related to "core.precomposeUnicode" (which wants to try + * to hide NFD completely and treat everything as NFC). Here, we + * don't know what the value the client has (or will have) for this + * config setting when they make a query, so assume the worst and + * emit both when the OS gives us an NFD path. + */ +static void my_add_path(struct fsmonitor_batch *batch, const char *path) +{ + char *composed; + + /* add the NFC or NFD path as received from the OS */ + fsmonitor_batch__add_path(batch, path); + + /* if NFD, also add the corresponding NFC spelling */ + composed = (char *)precompose_string_if_needed(path); + if (!composed || composed == path) + return; + + fsmonitor_batch__add_path(batch, composed); + free(composed); +} + + +static void fsevent_callback(ConstFSEventStreamRef streamRef UNUSED, + void *ctx, + size_t num_of_events, + void *event_paths, + const FSEventStreamEventFlags event_flags[], + const FSEventStreamEventId event_ids[] UNUSED) +{ + struct fsmonitor_daemon_state *state = ctx; + struct fsm_listen_data *data = state->listen_data; + char **paths = (char **)event_paths; + struct fsmonitor_batch *batch = NULL; + struct string_list cookie_list = STRING_LIST_INIT_DUP; + const char *path_k; + const char *slash; + char *resolved = NULL; + struct strbuf tmp = STRBUF_INIT; + int k; + + /* + * Build a list of all filesystem changes into a private/local + * list and without holding any locks. + */ + for (k = 0; k < num_of_events; k++) { + /* + * On Mac, we receive an array of absolute paths. + */ + free(resolved); + resolved = fsmonitor__resolve_alias(paths[k], &state->alias); + if (resolved) + path_k = resolved; + else + path_k = paths[k]; + + /* + * If you want to debug FSEvents, log them to GIT_TRACE_FSMONITOR. + * Please don't log them to Trace2. + * + * trace_printf_key(&trace_fsmonitor, "Path: '%s'", path_k); + */ + + /* + * If event[k] is marked as dropped, we assume that we have + * lost sync with the filesystem and should flush our cached + * data. We need to: + * + * [1] Abort/wake any client threads waiting for a cookie and + * flush the cached state data (the current token), and + * create a new token. + * + * [2] Discard the batch that we were locally building (since + * they are conceptually relative to the just flushed + * token). + */ + if (ef_is_dropped(event_flags[k])) { + if (trace_pass_fl(&trace_fsmonitor)) + log_flags_set(path_k, event_flags[k]); + + fsmonitor_force_resync(state); + fsmonitor_batch__free_list(batch); + string_list_clear(&cookie_list, 0); + batch = NULL; + + /* + * We assume that any events that we received + * in this callback after this dropped event + * may still be valid, so we continue rather + * than break. (And just in case there is a + * delete of ".git" hiding in there.) + */ + continue; + } + + if (ef_is_root_changed(event_flags[k])) { + /* + * The spelling of the pathname of the root directory + * has changed. This includes the name of the root + * directory itself or of any parent directory in the + * path. + * + * (There may be other conditions that throw this, + * but I couldn't find any information on it.) + * + * Force a shutdown now and avoid things getting + * out of sync. The Unix domain socket is inside + * the .git directory and a spelling change will make + * it hard for clients to rendezvous with us. + */ + trace_printf_key(&trace_fsmonitor, + "event: root changed"); + goto force_shutdown; + } + + if (ef_ignore_xattr(event_flags[k])) { + trace_printf_key(&trace_fsmonitor, + "ignore-xattr: '%s', flags=0x%x", + path_k, event_flags[k]); + continue; + } + + switch (fsmonitor_classify_path_absolute(state, path_k)) { + + case IS_INSIDE_DOT_GIT_WITH_COOKIE_PREFIX: + case IS_INSIDE_GITDIR_WITH_COOKIE_PREFIX: + /* special case cookie files within .git or gitdir */ + + /* Use just the filename of the cookie file. */ + slash = find_last_dir_sep(path_k); + string_list_append(&cookie_list, + slash ? slash + 1 : path_k); + break; + + case IS_INSIDE_DOT_GIT: + case IS_INSIDE_GITDIR: + /* ignore all other paths inside of .git or gitdir */ + break; + + case IS_DOT_GIT: + case IS_GITDIR: + /* + * If .git directory is deleted or renamed away, + * we have to quit. + */ + if (ef_is_root_delete(event_flags[k])) { + trace_printf_key(&trace_fsmonitor, + "event: gitdir removed"); + goto force_shutdown; + } + if (ef_is_root_renamed(event_flags[k])) { + trace_printf_key(&trace_fsmonitor, + "event: gitdir renamed"); + goto force_shutdown; + } + break; + + case IS_WORKDIR_PATH: + /* try to queue normal pathnames */ + + if (trace_pass_fl(&trace_fsmonitor)) + log_flags_set(path_k, event_flags[k]); + + /* + * Because of the implicit "binning" (the + * kernel calls us at a given frequency) and + * de-duping (the kernel is free to combine + * multiple events for a given pathname), an + * individual fsevent could be marked as both + * a file and directory. Add it to the queue + * with both spellings so that the client will + * know how much to invalidate/refresh. + */ + + if (event_flags[k] & (kFSEventStreamEventFlagItemIsFile | kFSEventStreamEventFlagItemIsSymlink)) { + const char *rel = path_k + + state->path_worktree_watch.len + 1; + + if (!batch) + batch = fsmonitor_batch__new(); + my_add_path(batch, rel); + } + + if (event_flags[k] & kFSEventStreamEventFlagItemIsDir) { + const char *rel = path_k + + state->path_worktree_watch.len + 1; + + strbuf_reset(&tmp); + strbuf_addstr(&tmp, rel); + strbuf_addch(&tmp, '/'); + + if (!batch) + batch = fsmonitor_batch__new(); + my_add_path(batch, tmp.buf); + } + + break; + + case IS_OUTSIDE_CONE: + default: + trace_printf_key(&trace_fsmonitor, + "ignoring '%s'", path_k); + break; + } + } + + free(resolved); + fsmonitor_publish(state, batch, &cookie_list); + string_list_clear(&cookie_list, 0); + strbuf_release(&tmp); + return; + +force_shutdown: + free(resolved); + fsmonitor_batch__free_list(batch); + string_list_clear(&cookie_list, 0); + + pthread_mutex_lock(&data->dq_lock); + data->shutdown_style = FORCE_SHUTDOWN; + pthread_cond_broadcast(&data->dq_finished); + pthread_mutex_unlock(&data->dq_lock); + + strbuf_release(&tmp); + return; +} + +/* + * In the call to `FSEventStreamCreate()` to setup our watch, the + * `latency` argument determines the frequency of calls to our callback + * with new FS events. Too slow and events get dropped; too fast and + * we burn CPU unnecessarily. Since it is rather obscure, I don't + * think this needs to be a config setting. I've done extensive + * testing on my systems and chosen the value below. It gives good + * results and I've not seen any dropped events. + * + * With a latency of 0.1, I was seeing lots of dropped events during + * the "touch 100000" files test within t/perf/p7519, but with a + * latency of 0.001 I did not see any dropped events. So I'm going + * to assume that this is the "correct" value. + * + * https://developer.apple.com/documentation/coreservices/1443980-fseventstreamcreate + */ + +int fsm_listen__ctor(struct fsmonitor_daemon_state *state) +{ + FSEventStreamCreateFlags flags = kFSEventStreamCreateFlagNoDefer | + kFSEventStreamCreateFlagWatchRoot | + kFSEventStreamCreateFlagFileEvents; + FSEventStreamContext ctx = { + 0, + state, + NULL, + NULL, + NULL + }; + struct fsm_listen_data *data; + const void *dir_array[2]; + + CALLOC_ARRAY(data, 1); + state->listen_data = data; + + data->cfsr_worktree_path = CFStringCreateWithCString( + NULL, state->path_worktree_watch.buf, kCFStringEncodingUTF8); + dir_array[data->nr_paths_watching++] = data->cfsr_worktree_path; + + if (state->nr_paths_watching > 1) { + data->cfsr_gitdir_path = CFStringCreateWithCString( + NULL, state->path_gitdir_watch.buf, + kCFStringEncodingUTF8); + dir_array[data->nr_paths_watching++] = data->cfsr_gitdir_path; + } + + data->cfar_paths_to_watch = CFArrayCreate(NULL, dir_array, + data->nr_paths_watching, + NULL); + data->stream = FSEventStreamCreate(NULL, fsevent_callback, &ctx, + data->cfar_paths_to_watch, + kFSEventStreamEventIdSinceNow, + 0.001, flags); + if (!data->stream) + goto failed; + + return 0; + +failed: + error(_("Unable to create FSEventStream.")); + + FREE_AND_NULL(state->listen_data); + return -1; +} + +void fsm_listen__dtor(struct fsmonitor_daemon_state *state) +{ + struct fsm_listen_data *data; + + if (!state || !state->listen_data) + return; + + data = state->listen_data; + + if (data->stream) { + if (data->stream_started) + FSEventStreamStop(data->stream); + if (data->stream_scheduled) + FSEventStreamInvalidate(data->stream); + FSEventStreamRelease(data->stream); + } + + if (data->dq) + dispatch_release(data->dq); + pthread_cond_destroy(&data->dq_finished); + pthread_mutex_destroy(&data->dq_lock); + + FREE_AND_NULL(state->listen_data); +} + +void fsm_listen__stop_async(struct fsmonitor_daemon_state *state) +{ + struct fsm_listen_data *data; + + data = state->listen_data; + + pthread_mutex_lock(&data->dq_lock); + data->shutdown_style = SHUTDOWN_EVENT; + pthread_cond_broadcast(&data->dq_finished); + pthread_mutex_unlock(&data->dq_lock); +} + +void fsm_listen__loop(struct fsmonitor_daemon_state *state) +{ + struct fsm_listen_data *data; + + data = state->listen_data; + + pthread_mutex_init(&data->dq_lock, NULL); + pthread_cond_init(&data->dq_finished, NULL); + data->dq = dispatch_queue_create("FSMonitor", NULL); + + FSEventStreamSetDispatchQueue(data->stream, data->dq); + data->stream_scheduled = 1; + + if (!FSEventStreamStart(data->stream)) { + error(_("Failed to start the FSEventStream")); + goto force_error_stop_without_loop; + } + data->stream_started = 1; + + pthread_mutex_lock(&data->dq_lock); + pthread_cond_wait(&data->dq_finished, &data->dq_lock); + pthread_mutex_unlock(&data->dq_lock); + + switch (data->shutdown_style) { + case FORCE_ERROR_STOP: + state->listen_error_code = -1; + /* fall thru */ + case FORCE_SHUTDOWN: + ipc_server_stop_async(state->ipc_server_data); + /* fall thru */ + case SHUTDOWN_EVENT: + default: + break; + } + return; + +force_error_stop_without_loop: + state->listen_error_code = -1; + ipc_server_stop_async(state->ipc_server_data); + return; +} |